C-F bond integration in polymeric carbon nitride enables oxygen-tolerant photocatalytic reduction of NO to N2

The selective photocatalytic decomposition of NO under oxygen-rich conditions presents a significant challenge, largely due to the preferential reduction of O2 over NO. To overcome this limitation, we develop an F-modified polymeric carbon nitride catalyst (e-FCN). Under visible light irradiation in simulated ambient air (20% O2), the e-FCN catalyst achieves 85% NO conversion with 92% selectivity toward N2. It exhibits high apparent quantum yields for N2 formation (29.1% at 365 nm and ≥ 9.9% between 405 and 465 nm) and maintains its performance over 12 consecutive cycles without deactivation. Mechanistic investigations indicate that the incorporation of a C–F bond suppresses the detrimental C=O formation from O2 activation, thereby passivating the catalyst toward O2. Concurrently, e-FCN selectively adsorbs NO and promotes N–N coupling between adjacent NO molecules, ultimately converting NO to N2 via an N2O intermediate. This synergy of selective NO adsorption and controlled decomposition enables selective and oxygen-tolerant photocatalytic NO decomposition. Incorporating C–F bond into polymeric carbon nitride enables oxygen-tolerant photocatalytic NO reduction to N2. This occurs via preferential NO adsorption over O2, N–N coupling between adjacent NO molecules, and subsequent N2O intermediate reduction.